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BU629 ALF 4.0 building performance index calculator


Product Description

ALF 4.0 (Annual Loss Factor) is an online tool for determining the building performance index (BPI) of a house design. The calculator can be used to demonstrate that a specific house design complies with New Zealand Building Code clause H1 Energy efficiency.

ALF 4.0 is an updated and completely redesigned version of the older ALF 3.2 calculator. This bulletin replaces Bulletin 555 A guide to ALF 3.2.

This bulletin covers: 

  • getting started
  • entering data to find the BPI
  • results and reports
  • improving/optimising energy efficiency in design
  • energy cost and moisture
  • using ALF 4.0 for existing houses
  • ALF 4.0 web browser requirements.
Product Information
Publication date 2 October 2018
Product type Bulletin
Availability Available
Product code BU629